The overall objective of this project is to capitalize on the unique features of the lizard myogenic system. The study involves time lapse cinematography of developing muscle cultures in an attempt to describe morphological and behavioral changes that characterize muscle differentiation. Changes in cell surface morphology, correlated with the above, are being studied using the scanning electron microscope and transmission electron microscope. Density dependent variables in muscle differentiation and the appearance of proteins characteristic of the differentiated muscle cell are being studied in this system.